What I have learned studying comments from the technical experts on the sprinter forum...On the scangauge II, boost refers to how hard the turbocharger is working, and does not correlate directly to mpg, but rather more closely correlates to the load on the engine based on how you drive. if you monitor gph and lod on the scangauge and downshift to try and keep the lod below 75-80, your mileage will improve. lugging a diesel at lower than optimal rpms (as many gasoline engine experienced drivers tend to do by just putting the Sprinter in (D)rive and never gearing down) creates high lod, lots of smoke and soot, which gets trapped by the dpf in the sprinter and causes problems. never drive below 2,400 rpm with the v6/5-speed, nor above 3,200 to 3,400 rpm. gear down to rev it up to this range when your lod increases to 80+ and stays there more than a few seconds, and watch the lod and gph (gallons per hour) on the scangauge II. you'll find that you burn fewer gallons per hour by keeping the rpm's up and the lod lower. at low rpms, you will not generate the airflow nor higher exhaust gas temperatures necessary to keep the emissions systems working properly. Lots more detail over on the sprinter-source forum.

Definitely understand towing and general weight impact to MPG, does anyone have knowledge related to MPG impact for having a scooter/motorcycle on the hitch?

Related, is it correct that the allowed 'dead weight' on the hitch is 10% of the towing capacity? So for the 2401W MBS it would be a max of 420# (10% of 4200#) to include all weight including the rack?

Definitely understand towing and general weight impact to MPG, does anyone have knowledge related to MPG impact for having a scooter/motorcycle on the hitch?

Related, is it correct that the allowed 'dead weight' on the hitch is 10% of the towing capacity? So for the 2401W MBS it would be a max of 420# (10% of 4200#) to include all weight including the rack?

as long as with everything else it doesn't exceed your max allowed loaded vehicle weight of 11030# (GVWR ), I would say ( not GCWR which is for towed whatever )

also pay attention to the GAWR REAR of 7720#

to further clarify, weigh your vehicle as normally loaded, then see whether adding your scooter exceeds either of the above limits

as long as with everything else it doesn't exceed your max allowed loaded vehicle weight of 11030# (GVWR ), I would say ( not GCWR which is for towed whatever )

also pay attention to the GAWR REAR of 7720#

to further clarify, weigh your vehicle as normally loaded, then see whether adding your scooter exceeds either of the above limits

Just weighed our 2015 Solera 24R on the CAT Certified Scales near our house and the rig was 10,000 lbs. even with less than 100 lbs of cargo, no water, gray and black tanks dry, 6 gal. of diesel, and a 1/4 tank of propane

Hey Beach Bums - got some data for you. Recent trip to Oregon coast towing an 09 Smart Car which weighs 1,700 lbs. First 200 miles averaged 40 mph due to rolling slow down traffic on I-5. Averaged 15.3 mpg. Return trip averaged closer to 60 mph. Average 14.6 mpg. Both are within 1 or less mile per gallon than without the Smart Car behind us. Our 2015 Solera, having the drag coefficient of a barn door, proved to us that slower speed has more to do with gas mileage than adding a light tow vehicle.

Also, did some precise figuring on DEF consumption. Filled the DEF tank until I could see the DEF at the bottom of the fill tube. After going through 90.2 gallons of diesel, the tank took 82 ounces of DEF to reach the same level. Pretty close to what I've read elsewhere; figure 1 ounce of DEF for each gallon of fuel burn.

PS: Consider myself lucky surviving to age 68 pretty much intact despite enjoying spirited motorcycles and Marlboros for many years. Less acute peripheral vision, slowing reflexes and texting car drivers made the adrenalin high of two wheeling unacceptably riskier. Driving a Smartie, though quirky, is oddly fulfilling. Consider switching. Your RV won't mind towing one any more than it would a Harley.

I posted this elsewhere ... but to make it easy -> 2009 Smart, Passion model, 19,000 miles, one owner; paid $7,200. Found on Craigslist ... as was the Roadmaster tow bar at an estate sale ($50) ... color seems to match Solera body paint very well ... Smarts have good reliability IF they don't overheat ... no low coolant warning light, only overheat warning light - if on freeway an overheat goes on and you drive another mile to an exit, you may have toasted the engine ... sign of prior overheat might be white smoke/steam in exhaust usually blown head gasket.

Drive several if you're interested ... all seemed slightly different in how the automatic transmission performed ... pretty much a buyers market for these as opposed to Honda Fit (towable with automatic) and Tracker/Sidekick 4wd with transfer case (towable with automatic).

Feel free to send PM (private message) for more info ... this is kinda off topic for this portion of the Forum.

1500 miles over ~4 days from North to South....Low was 10 mpg and high was 14.1. The unit was empty less wife and I and minimal clothing. The 10 mpg was somewhat expected as we were pushing hard to get to a safe camping location before dark as all of our running lights were not working....

Of concern to be watched closer is when the low fuel light comes on. The manual conveys it comes on with only 5 gallons diesel left. Think it comes on early. As I traveled another 50 miles and still had 3.5 gallons left in the tank....not possible that my last miles were at that type of mpg.

1500 miles over ~4 days from North to South....Low was 10 mpg and high was 14.1. The unit was empty less wife and I and minimal clothing. The 10 mpg was somewhat expected as we were pushing hard to get to a safe camping location before dark as all of our running lights were not working....

Of concern to be watched closer is when the low fuel light comes on. The manual conveys it comes on with only 5 gallons diesel left. Think it comes on early. As I traveled another 50 miles and still had 3.5 gallons left in the tank....not possible that my last miles were at that type of mpg.

The low fuel light on mine seems to come on with approx. 6 gallons remaining. I don't push it though. I might drive another 30 miles to find fuel. Don't won't to run out with the diesel. Driving across Texas from East to West I carry a five gallon container in the toad just in case. Normal average towing 11.8/12.8; sometimes higher depending on terrain.